Stop loss/profit targets while doing walk forward

I'm curious on how others do their stop loss and profit targets on stocks to have moved a large dollar amount when doing backtest/walk forward? Do you just set a very large range for parameters for these settings? Do you use %? When testing a large moving stock like GOOG (which has literally moved 500 pts since going public) I do better and better as it gets closer to present but my initial results are usually weak.

Currently I've been using price * TickSize for my stops/pts but I'm wondering if I need to go really wide or if there is another solution?